Unpublished observations from this laboratory strongly suggest that neuronal activity in the hypothalamic region of the rat brain is depressed during an acute exposure to methyl methacrylate monomer vapor. The object of this study is to evaluate the effects of methyl methacrylate monomer on the central nervous system of the Sprague Dawley rat. We propose to study the effects of an acute exposure to the vapor by monitoring the cortical EEG and multiple unit activity from those regions of the brain involved in the regulation of gastrointestinal function. We intend to determine if chronic exposure to the vapor also alters those neuronal structures found to be acutely affected and if possible to determine the dose level at which this effect is observed.